In normal practice, digital signals are converted into streams of modulation symbols, for example using a modulation scheme such as QPSK, and then modulated onto RF carrier signals. Receivers that are configured to handle signals that have been modulated in this way attempt to isolate a wanted received carrier signal and then demodulate the stream of symbols from the RF carrier signal. However, it is likely that the carrier signal will reach the receiver via a number of different paths, with the result that a number of versions of the carrier signal arrive at the receiver, all at different delays. This is the well known phenomenon of multipath propagation, which gives rise to intersymbol interference (ISI) in the demodulated signal. That is to say, the delay between two multipath components can be such that at some given instant, the receiver experiences different symbols from the two paths. It is well known to use an equaliser or a RAKE receiver to compensate or correct for intersymbol interference.